Confocal microscope

Abstract

A confocal microscope includes an illumination optical system configured to uniformly illuminate at least part of a first confocal stop with a light beam from a light source, a first collection optical system configured to collect a light beam passing through the first confocal stop onto a specimen, a second collection optical system configured to collect a light beam from the specimen onto a second confocal stop, a detection unit configured to detect a light beam passing through the second confocal stop, and a light intensity control member provided to at least one of the first collection optical system and the second collection optical system and having a transmittance of a first region including an optical axis that is lower than a transmittance of a second region around the first region.

What is claimed is: 
     
       1. A confocal microscope comprising:
 an illumination optical system configured to uniformly illuminate at least part of a first confocal stop; 
 a first collection optical system configured to collect a light beam passing through the first confocal stop onto a specimen; 
 a second collection optical system configured to collect a light beam from the specimen onto a second confocal stop; 
 a detection unit configured to detect a light beam passing through the second confocal stop; 
 a first light intensity control member provided to at least one of the first collection optical system and the second collection optical system and having a transmittance of a first region including an optical axis that is lower than a transmittance of a second region around the first region; and 
 a second light intensity control member provided to the illumination optical system and having a transmittance of a third region including the optical axis that is lower than a transmittance of a fourth region around the third region. 
 
     
     
       2. The confocal microscope according to  claim 1 , wherein the first light intensity control member is disposed at the pupil position of at least one of the first collection optical system and the second collection optical system or a position conjugate to the pupil position. 
     
     
       3. The confocal microscope according to  claim 1 , wherein the second light intensity control member is disposed at the pupil position of the illumination optical system or a position conjugate to the pupil position. 
     
     
       4. The confocal microscope according to  claim 1 , wherein:
 the third region of the second light intensity control member has a circular shape centering around the optical axis with a second radius, and 
 the second radius is not larger than four-fifths of the numerical aperture of the first collection optical system. 
 
     
     
       5. The confocal microscope according to  claim 1 , wherein:
 the first confocal stop includes a multi-pinhole array including a plurality of pinholes, and 
 the illumination optical system is configured to perform Koehler illumination on the first confocal stop. 
 
     
     
       6. The confocal microscope according to  claim 1 , wherein the first collection optical system includes a collimating lens, a dichroic mirror, and an objective lens. 
     
     
       7. The confocal microscope according to  claim 6 , wherein the first light intensity control member is disposed between the collimating lens and the dichroic mirror. 
     
     
       8. The confocal microscope according to  claim 1 , wherein the second collection optical system includes an objective lens, a dichroic mirror, and an imaging lens. 
     
     
       9. The confocal microscope according to  claim 8 , wherein the first light intensity control member is disposed between the dichroic mirror and the imaging lens. 
     
     
       10. The confocal microscope according to  claim 1 , wherein:
 the illumination optical system includes a relay lens and a collimating lens, and 
 the second light intensity control member is disposed between the relay lens and the collimating lens. 
 
     
     
       11. The confocal microscope according to  claim 1 , wherein the confocal microscope is configured to acquire information of the specimen that fluoresces with the light beam collected by the first collection optical system. 
     
     
       12. The confocal microscope according to  claim 1 , further comprising a third light intensity control member provided to the first collection optical system and having a transmittance of a fifth region including the optical axis that is lower than a transmittance of a sixth region around the fifth region, the first light intensity control member being provided to the second collection optical system. 
     
     
       13. A confocal microscope comprising:
 an illumination optical system configured to uniformly illuminate at least part of a first confocal stop; 
 a first collection optical system configured to collect a light beam passing through the first confocal stop onto a specimen; 
 a second collection optical system configured to collect a light beam from the specimen onto a second confocal stop; 
 a detection unit configured to detect a light beam passing through the second confocal stop; and 
 a light intensity control member provided to at least one of the first collection optical system and the second collection optical system and having a transmittance of a first region including an optical axis that is lower than a transmittance of a second region around the first region, 
 wherein: 
 the first region of the light intensity control member has a circular shape centering around the optical axis with a predetermined radius, and 
 the predetermined radius is not larger than three-fifths of the numerical aperture of the first collection optical system or the second collection optical system. 
 
     
     
       14. The confocal microscope according to  claim 13 , wherein:
 the first region of the light intensity control member has a circular shape centering around the optical axis with a predetermined radius, and the second region has an annular shape around the first region centering around the optical axis, and 
 the predetermined radius of the first region is not larger than three-fifths of a radius of a circumference of the second region centering around the optical axis. 
 
     
     
       15. A confocal microscope comprising:
 an illumination optical system configured to uniformly illuminate at least part of a first confocal stop; 
 a first collection optical system configured to collect a light beam passing through the first confocal stop onto a specimen; 
 a second collection optical system configured to collect a light beam from the specimen onto a second confocal stop; 
 a detection unit configured to detect a light beam passing through the second confocal stop; and 
 a light intensity control member provided to at least one of the first collection optical system and the second collection optical system and having a transmittance of a first region including an optical axis that is lower than a transmittance of a second region around the first region, 
 wherein when a ratio of the numerical aperture of the illumination optical system on the first confocal stop side to the numerical aperture of the first collection optical system on the first confocal stop side is represented by σ, the ratio satisfies a range of 0.3≦σ≦1.